Server with heat pipe cooling

ABSTRACT

A server includes a tray that has a front portion and a back portion. A motherboard is disposed in the front portion of the tray and the motherboard is coupled to a heat sink. A fan is disposed in the back portion of the tray. A hard drive is disposed between the motherboard and the fan and the hard drive is operatively connected to the motherboard. The server also includes a heat pipe that has a body longitudinally bounded by an inlet and an outlet. The inlet is coupled to the heat sink, while the outlet is coupled to the fan. The body of the heat pipe extends past the hard drive. A power supply is also disposed in the tray and is operatively connected to the motherboard, the fan, and the hard drive.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims the priority benefit of U.S. Provisional Application Ser. No. 61/780,770, titled “Server with Heat Pipe Cooling,” filed Mar. 13, 2013, the disclosure of which is incorporated herein by reference.

BACKGROUND

As companies create and process more and more data, the data storage systems required to handle the data must provide faster data access and higher data storage capacities. Data storage systems are implemented in data centers having large numbers of servers in rack-mount trays. The servers manage access to centralized resources or services in a network. The data centers house several servers at the same time, often storing each server in chassis, such as a tray or blade. Several trays are commonly stored in a single cabinet, and a plurality of cabinets are often arranged in rows separated by an aisle.

As a server's processing power increases, so does the heat that is radiated from server processors and other circuitry. Heat can damage various components within a chassis, such as temperature sensitive hard drives, that have a specific temperature window for optimal operation. Extremely high temperatures in certain service aisles can create health risks for data center employees that must enter the aisles to manage cables, fix connection issues or perform other tasks such as routine maintenance. The Occupational Safety and Health Administration (OSHA) enforces regulations that prevent data center employees from working in environments that exceed a certain temperature.

Servers of the prior art typically feature input/output (I/O) terminals that face into the hot aisle. Such servers do so because they lack the ability to be turned around so that their I/O terminals face into the cold aisle (i.e., to allow data center employees to work in the cold aisle rather than the hot aisle). When a server of the prior art is simply turned around such that its I/O terminals face into the cold aisle, the motherboard must also be located next to the cold aisle due to inherent connector limitations. The motherboard cannot simply be positioned downstream from the temperature sensitive devices because doing so places the motherboard too far from the I/O terminals. Accordingly, turning the chassis around places the temperature sensitive device downstream from the heat-generating motherboard. When air is passed through the chassis to exhaust the heat into the hot aisle, the hot air radiating from the motherboard is carried into contact with the hard drive or other temperature sensitive device.

The air may be blown into the server by a computer room air conditioner (CRAG) or computer room air handler (CRAH). The air may also be directed into the server by one or more externals fans that are located outside of the server tray and face into the chassis. Alternatively, rather than being blown through the chassis, the air may be drawn through the chassis by a fan located at its rear. In any such configuration, temperature sensitive devices are exposed dangerously high temperatures that can cause them to fail.

Given these shortcomings in the art, there is a need in the art for servers with improved cooling systems that increase cooling efficiencies while reducing heat exposure for sensitive components and data center employees.

SUMMARY

Heat pipes are utilized in a server tray to transport heat from high radiating devices around and/or away from temperature sensitive devices. The heat pipes may provide the heat to a heat sink, radiator, fan, or other device in the rear of the server tray. The server tray includes a front portion and a back portion. A motherboard is disposed in the front portion of the tray and is coupled to a heat sink. A fan is disposed in the back portion of the tray, and a hard drive is disposed between the motherboard and the fan. The hard drive may be connected to the motherboard. The server tray includes one or more heat pipes that have a body longitudinally bounded by an inlet and an outlet. The inlet may be coupled to the heat sink, while the outlet is coupled to the fan. The body of the heat pipe extends past the hard drive or other components sensitive to heat.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a perspective view of an exemplary server tray in accordance with the presently claimed invention.

FIG. 2 is a side view of an exemplary cooling system in accordance with the presently claimed invention.

FIG. 3 is a top view of an exemplary cooling system in accordance with the presently claimed invention.

FIG. 4 is a method for cooling a server with a heat pipe.

DETAILED DESCRIPTION

A server tray with an improved cooling system utilizing heat pipes is provided. Heat pipes are utilized in a server tray to transport heat from high radiating devices around and/or away from temperature sensitive devices. The heat pipes carry the heat from a heat sink to a radiator in the rear of the server tray.

The server may manage access to centralized resources or services in a network. The server may be stored in a data center. Although data centers are discussed herein for illustrative purposes, the present technology may be useful for other entities as well.

As described below in further detail, the present invention allows the hard drive and other sensitive components to be ventilated and cooled without exposing them to dangerously hot air. The presently claimed invention does so by allowing the I/O terminals to face into the cold aisle and using heat pipes to transport heat from high radiating devices around and/or away from temperature sensitive devices that are downstream from the high radiating devices. Because the I/O terminals face into the cold aisle, data center employees can work in the cold aisle rather than the hot aisle. As a result, the presently claimed invention reduces safety risks to employees and allows data centers to easily comply with OSHA regulations

FIG. 1 shows a perspective view of an exemplary server tray that allows its I/O terminal to face into the cold aisle rather than the hot aisle. A server tray 100 includes a tray 105 having a front portion 110 and a back portion 120. Server 100 also includes a motherboard 140 disposed in front portion 110 of tray 105. Motherboard 140 is coupled to a heat sink 150. Heat sink 150 draws heat from motherboard 140. In embodiments, the heat sink may include a copper block that holds the heat pipes to the CPU by engaging the standard heat sink mounting provisions on the motherboard. In embodiments, heat sink 150 may be made from copper, aluminum, or any other material that provides for heat convention from the heat sink to the air between the sink prongs. The heat sink 150 may have any dimension and design that is suitable to draw a sufficient amount of heat from the motherboard. A fan 160 is disposed in the back portion of tray 105. A hard drive 170 is disposed between motherboard 140 and fan 160. Hard drive 170 is operatively connected to motherboard 140.

Heat pipes 180 are connected between heat sinks 150 and travel through the tray 105 to rear fan 120. As shown, the heat pipes navigate the tray so as to travel underneath or away from the hard drives 170. Heat pipes 180 are insulated to help prevent heat from affecting the temperature, and corresponding performance, of hard drives 170 and other heat sensitive devices.

Heat sink 150 is coupled to fan 160 through heat pipe 180. Server 100 may include an input/output (I/O) terminal 130 disposed in front portion 100 of tray 105. I/O terminal 130 may be operatively connected to motherboard 140. A power supply 190 may be disposed in tray 105. Power supply 190 may be operatively connected to motherboard 140, fan 160, and hard drive 170. Tray 105 may be installed in a rack (not shown) having multiple trays 105, each tray 105 having multiple hard drives 170 for storing data. Because I/O terminal 130 may face into the cold aisle rather than the hot aisle, data center employees may work on cabling or connection issues without having to withstand dangerous temperatures in the hot aisle. Accordingly, the presently claimed invention allows for significantly increased compliance with existing OSHA regulations.

FIG. 2 shows a side view of an exemplary cooling system in accordance with the presently claimed invention. The cooling system illustrated in FIGS. 2 and 3 represent a side view and top view, respectively, of the heat pipes 180 of FIG. 1 with most of the other tray components removed. Cooling system 200 includes a heat pipe 210 having a body longitudinally bounded by an inlet 220 and an outlet 230. Heat pipe 210 may include copper or any number of other suitable materials that will be readily recognized by a person of ordinary skill in the art. Specifically, heat pipe 210 may be made with any other material that can transfer and/or conduct heat, such as silver or gold. Inlet 220 is coupled to a heat sink 240, while outlet 230 is coupled to a fan 250. The body of heat pipe 210 extends past hard drive 170 of FIG. 1 along the length of tray 105. The size and length of heat pipe 210 may be selected based on design considerations. For example, a heat pipe 210 may be selected to provide the shortest length possible between heat sink 240 and fan 250 to minimize the heat lost within the system. The present invention may be implemented with a variety of heat pipe sizes and shapes, based on the layout of the chassis, the environment in which heat pipe 210 is used, and how much heat needs to be transferred. For example, in an embodiment, the present invention may utilize four 8 mm copper heat pipes 210.

FIG. 3 is a top view of another exemplary cooling system in accordance with the presently claimed invention. Cooling system 300 may include a plurality of heat pipes 310, each having a body longitudinally bounded by an inlet 320 and an outlet 330. Inlet 320 is coupled to a heat sink 340, while outlet 330 is coupled to a fan 350. Each inlet 320 may be coupled to the same heat sink 340, or they may be coupled to multiple heat sinks 340 individually or in groups. The body of each heat pipe 310 may extend past hard drive 170 of FIG. 1 along the length of tray 105. Heat pipes 310 may be manufactured using known heating, casting, and cooling processes.

Referring back to FIG. 1, heat pipe 180 may extend past hard drive 170 while being disposed beneath hard drive 170. Heat pipe 180 may also extend past hard drive 170 while being disposed adjacent to or above hard drive 170. As persons of ordinary skill in the art will readily recognize, any number of configurations for heat pipe 180 are suitable so long as the heat generated by motherboard 140 is substantially limited from contacting hard drive 170. Because the heat radiating from motherboard 140 travels through heat pipe 180 and is exhausted out the back of tray 105 by fan 160, the hot air may be concentrated in the hot aisle without heating sensitive components like hard drive 170. I/O terminal 130 may also face into or be accessible from the cold aisle, which allows data center employees to avoid working in the hot aisle.

Because the data center employees can avoid working in the hot aisle, data centers can more easily comply with OSHA regulations that limit when a data center employee may enter the hot aisle. For example, OSHA's maximum permissible wet-bulb globe temperature (WBGT) in the hot aisle is 86 degrees Fahrenheit when doing continuous work and 90 degrees Fahrenheit with a regimen of 25% work and 75% rest. Cooling efficiencies are highest when the hot aisle is maintained at over 100 degrees Fahrenheit. The presently claimed invention allows the hot aisle to remain over 100 degrees Fahrenheit while simultaneously allowing datacenter workers to work in the cold aisle—an environment within acceptable OSHA limits. Accordingly, the presently claimed invention provides increased cooling efficiencies, reduced health risks to data center employees, and increased compliance with OSHA regulations, all while substantially mitigating heat-induced damage to hard drives and other sensitive components.

FIG. 4 is a method for cooling a server with a heat pipe. The method of FIGURE begins with coupling a first end of the heat pipe in a server to a heat sink at step 410. The second end of the heat pipe may be coupled to a fan at step 420. The heat pipe may be positioned such that the heat pipe directs heat away from the hard drive at step 430. For example, the heat pipe may be positioned above, below or adjacent to the hard drive, but not touching the hard drive. Heat is transferred from the heat sink towards the fan through the heat pipe without exposing the hard drive to heat which affects the drive performance at step 440. It may be acceptable to expose the hard drive to a bit of radiation from the heat pipe, but the heat pipe will not be positioned such that the radiation coming off the heat pipe raises the temperature of the hard drive to a point at which performance of the hard drive may degrade.

The foregoing detailed description of the technology herein has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the technology to the precise form disclosed. Many modifications and variations are possible in light of the above teaching. The described embodiments were chosen in order to best explain the principles of the technology and its practical application to thereby enable others skilled in the art to best utilize the technology in various embodiments and with various modifications as are suited to the particular use contemplated. It is intended that the scope of the technology be defined by the claims appended hereto. 

What is claimed is:
 1. A server, comprising: a tray having a front portion and a back portion; a motherboard disposed in the front portion of the tray, the motherboard coupled to a heat sink; a fan disposed in the back portion of the tray; a hard drive disposed between the motherboard and the fan, the hard drive operatively connected to the motherboard; a heat pipe having a body longitudinally bounded by an inlet and an outlet, the inlet coupled to the heat sink, the outlet coupled to the fan, and the body extending past the hard drive; and a power supply disposed in the tray, the power supply operatively connected to the motherboard, the fan, and the hard drive.
 2. The server of claim 1, further comprising an input/output (I/O) terminal disposed in the front portion of the tray, the I/O terminal operatively connected to the motherboard.
 3. The server of claim 1, wherein the heat pipe includes copper.
 4. The server of claim 1, wherein the tray is installed in a rack having a plurality of trays, each tray having multiple hard drives for storing data.
 5. The server of claim 1, wherein the body of the heat pipe extends past the hard drive while being disposed beneath the hard drive.
 6. The server of claim 1, wherein the body of the heat pipe extends past the hard drive while being disposed above the hard drive.
 7. The server of claim 1, wherein the body of the heat pipe extends past the hard drive while being disposed adjacent to hard drive.
 8. A method for cooling a server component with a heat pipe, comprising: coupling a first end of the heat pipe in a server to a heat sink; coupling a second end of the heat pipe to a fan; routing the body of the heat pipe to direct heat away from the hard drive; and transferring heat from the heat sink towards the fan through the heat pipe, the heat pipe positioned to prevent exposing the hard drive to heat which affects the hard drive performance.
 9. The method of claim 8, wherein the body of the heat pipe extends past the hard drive while being disposed beneath the hard drive.
 10. The method of claim 8, wherein the body of the heat pipe extends past the hard drive while being disposed above the hard drive.
 11. The method of claim 8, wherein the body of the heat pipe extends past the hard drive while being disposed adjacent to hard drive.
 12. The method of claim 8, wherein the heat pipe includes copper. 